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991.
992.
Molecularly Imprinted Nanogels Acquire Stealth In Situ by Cloaking Themselves with Native Dysopsonic Proteins
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Prof. Dr. Toshifumi Takeuchi Dr. Yukiya Kitayama Reo Sasao Takuya Yamada Dr. Kazuko Toh Dr. Yu Matsumoto Prof. Dr. Kazunori Kataoka 《Angewandte Chemie (International ed. in English)》2017,56(25):7088-7092
Protein corona formation was regulated on the surface in vivo by molecular imprinting to enable polymeric nanogels to acquire stealth upon intravenous administration. Albumin, the most abundant protein in blood, was selected as a distinct protein component of protein corona for preparing molecularly imprinted nanogels (MIP-NGs) to form an albumin-rich protein corona. Intravital fluorescence resonance energy transfer imaging of rhodamine-labeled albumin and fluorescein-conjugated MIP-NGs showed that albumin was captured by MIP-NGs immediately after injection, forming an albumin-rich protein corona. MIP-NGs circulated in the blood longer than those of non-albumin-imprinted nanogels, with almost no retention in liver tissue. MIP-NGs also passively accumulated in tumor tissue. These data suggest that this strategy, based on regulation of the protein corona in vivo, may significantly influence the development of drug nanocarriers for cancer therapy. 相似文献
993.
Synthesis of polycarbosilanes having sugar‐derived structures as novel materials for cell cultivation
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Kozo Matsumoto Takanori Fujiwara Mitsuaki Goto Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2015,53(19):2267-2272
Polycarbosilanes with or without sugar‐derived structures in the polymer side chains were synthesized and their application to materials for cell cultivation was investigated. Polysilacyclobutanes having glucose‐derived moieties or N‐acetylglucosamine‐derived moieties (polyBMSB‐glucose and polyBMSB‐AGA) were synthesized by ene‐thiol reaction between precursor poly(1‐(3‐butenyl)?1‐methylsilacyclubane) (polyBMSB) and tetraacetylglucose or tetraacetylglucosamine having a thiol group at the anomeric position and the successive deprotection of the acetyl groups gave polycarbosilanes with sugar‐derived structures in the side chains. Poly(1‐(3‐hydroxybutyl)‐1‐methylsilacyclobutane) was synthesized by hydroboration/oxidation of the precursor polyBMSB. The cell cultivation efficiency using the polymers with or without sugar moieties was evaluated by cultivation of WRL cells on the polystyrene dishes coated with the polymers. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2267–2272 相似文献
994.
995.
Inside Back Cover: Studies on the Magnetic Ground State of a Spin Möbius Strip (Chem. Eur. J. 40/2016)
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996.
Radical copolymerization of N‐phenylmaleimide and diene monomers in competition with diels–alder reaction
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Akikazu Matsumoto Daisuke Yamamoto 《Journal of polymer science. Part A, Polymer chemistry》2016,54(22):3616-3625
Radical copolymerization of N‐phenylmaleimide (PhMI) is carried out with various diene monomers including naturally occurring compounds and the copolymers are efficiently produced by the suppression of Diels–Alder reaction as the competitive side reaction. Diene monomers with an exomethylene moiety and a fixed s‐trans diene structure, such as 3‐methylenecyclopentene and 4‐isopropyl‐1‐methyl‐3‐methylenecyclohexene, exhibit high copolymerization reactivity to produce a high‐molecular‐weight copolymer in a high yield. The copolymerization of sterically hindered noncyclic diene monomers, such as 2,4‐dimethyl‐1,3‐pentadiene and 2,4‐hexadiene, also results in the formation of a high‐molecular‐weight copolymer in a moderate yield. The NMR spectroscopy reveals that the obtained copolymers consist of predominant 1,4‐repeating structures for the corresponding diene unit. The copolymers have excellent thermal stability, that is, an onset temperature of decomposition over 330 °C and a glass transition temperature over 130 °C. The copolymerization reactivity of these diene monomers is discussed based on the results of the DFT calculations. The efficient copolymer formation in competition with Diels–Alder addition is investigated under various conditions of the temperature, solvents, and initiators used for the copolymerization. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3616–3625. 相似文献
997.
998.
K Isosaki N Seno I Matsumoto T Koyama S Moriguchi 《Journal of chromatography. A》1992,597(1-2):123-128
Methyl vinyl ether-maleic anhydride copolymer (MMAC) is a water-insoluble polymer with an acid anhydride group which reacts with amino groups of ligands to form stable amide bonds. MMAC was used to immobilize protein ligands on two kinds of supports, the wells of plastic microtitre plates for enzyme-linked immunosorbent assay and related methods, and gels for affinity adsorbents. The wells were first coated with MMAC and then allowed to react with proteins. The immobilization of proteins by this method was efficient and occurred in a dose-dependent manner. Shodex Et123, a gel having amino groups, was incubated with MMAC, and then the activated Shodex was used to immobilize high concentrations of proteins. Concanavalin A-Shodex thus obtained had high affinities and was successfully used for the high-performance liquid affinity chromatography of sugar derivatives on a short column. 相似文献
999.
Furukawa R. Uyama H. Matsumoto O. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1990,18(6):930-933
Carburizing and diamond deposition experiments were done on titanium, niobium, and molybdenum substrates with argon-methane-hydrogen gas mixture plasma jets at a pressure of 200 torr for various hydrogen concentrations. Diamond deposition was obtained at a volume of 7% hydrogen added to the plasma jet. The deposits were markedly different on the different metal substrates. Diamond deposits with habit planes were clearly observed on niobium and molybdenum, while the deposit on titanium consisted of ball-like particles. The emission spectra from the plasma jet were the same, for all the substrates, proving that the difference in the diamond deposit depends on the substrate characteristics. CH, C2, hydrogen, and carbon atoms were identified in the plasma jet. The difference in the deposits is attributed to the reactivity of carbon species in the plasma with the metal surface as well as to the solubility of hydrogen in metals 相似文献
1000.
In this article, the existence of additive BIB designs is discussed with direct and recursive constructions, together with investigation of a property of resolvability. Such designs can be used to construct infinite families of BIB designs. In particular, we obtain a series of B(sn, tsm, λt (tsm ? 1) (sn‐m ? 1)/[2(sm ? 1)]) for any positive integer λ, such that sn (sn ? 1) λ ≡ 0 (mod sm (sm ? 1) and for any positive integer t with 2 ≤ t ≤ sn‐m, where s is an odd prime power. Connections between additive BIB designs and other combinatorial objects such as multiply nested designs and perpendicular arrays are discussed. A construction of resolvable BIB designs with v = 4k is also proposed. © 2007 Wiley Periodicals, Inc. J Combin Designs 15: 235–254, 2007 相似文献